The Effect of Obesity on Dose of Dexmedetomidine When Administered With Fentanyl During Postoperative Mechanical Ventilation - Retrospective

Abstract

: We carried out a retrospective investigation on the effect of obesity on dexmedetomidine (DEX) requirements when administered with fentanyl (FEN) during mechanical ventilation after major surgeries. After Institutional Review Board approval, 14 obese patients with a body mass index (BMI) ≥ 30 kg/m 2 and the same number of non -obese patients with similar backgrounds to the obese patients were selected from medical records. Doses of DEX in the first 48 h or until the end of sedation or extubation were calculated for comparison. In addition to comparison of dosing between the groups, associations between total body weight (TBW), BMI, and lean body mass (LBM) values and doses of DEX (mcg/h), between BMI and various indices (i.e., amount per TBW per hour and amount per LBM per hour) of DEX doses, and between above indices of DEX and FEN doses were also examined. There were no significant differences in DEX dose indices between the groups. However, DEX requirements (mcg/h) were significantly increased with TBW (kg) (r = 0.51, P = 0.003), BMI (r = 0.49, P = 0.006) and LBM (kg) (r = 0.42, P = 0.02), which might have enhanced the DEX metabolism with physiological changes with obesity. These findings will be beneficial for future clinical pharmacological analysis of DEX.

Determination of the ED95 of a single bolus dose of dexmedetomidine for adequate sedation in obese or nonobese children and adolescents

“…3,31 Our results indicate that children with obesity required similar body-weight-based dose of dexmedetomidine (in mg kg À1 ) as normal-weight children. This result is consistent with the study by Obara and colleagues 12 in adult patients showing no significant difference in dexmedetomidine dosing between the groups with and without obesity in terms of dosing of dexmedetomidine using TBW or lean body weight calculator. We used TBW to calculate dexmedetomidine dosage, because the TBW scalar is the most practical method in clinical setting and has been widely used in paediatric patients.…”